A269039 Number of 5Xn 0..2 arrays with some element plus some horizontally, diagonally or antidiagonally adjacent neighbor totalling two exactly once.

0, 1944, 12228, 146064, 1326576, 13031664, 119790816, 1105914780, 9987532176, 89650751964, 796324353216, 7029528437100, 61650349082232, 537978900955440, 4672818187679448, 40427882184540648, 348530963947264848

Offset: 1

Author

R. H. Hardin, Feb 18 2016

Keywords

• nonn

Comments

Row 5 of A269035.

Examples

			Some solutions for n=4
..0..1..2..1. .0..0..0..1. .0..0..0..1. .2..1..0..0. .2..1..2..1
..2..1..2..1. .1..1..0..1. .0..0..0..0. .2..1..0..0. .0..1..0..1
..0..1..2..1. .0..0..0..1. .0..0..0..1. .2..1..0..1. .0..0..0..0
..2..1..2..2. .0..1..0..1. .0..0..0..1. .0..1..2..2. .1..0..1..2
..2..1..0..1. .0..1..2..1. .1..0..1..0. .2..1..2..1. .1..2..1..2
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A269035.

Formula

Empirical: a(n) = 12*a(n-1) +26*a(n-2) -566*a(n-3) -123*a(n-4) +8804*a(n-5) -4121*a(n-6) -59620*a(n-7) +55115*a(n-8) +183692*a(n-9) -256127*a(n-10) -211910*a(n-11) +498819*a(n-12) -48036*a(n-13) -371692*a(n-14) +214008*a(n-15) +43848*a(n-16) -64656*a(n-17) +8640*a(n-18) +5184*a(n-19) -1296*a(n-20) for n>22